Work proposed will deal: a) with the immunocytochemical identification of growth hormone and prolactin, at the light microscopic and electron microscopic level, in normal and adenomatous human hypophyses; b) with the possibility that there are qualitative differences between the action of cyclic AMP in normal vs. goitrous thyroids, as there appear to be qualitative differences with respect to the ionic requirements of adenylate cyclase in such glands; c) with the possibility that iodide exit from dispersed thyroid cell is by a carrier-mediated process rather than simple diffusion; d) with the role of iodinated lipid in the regulation of iodide transport in dispersed thyroid cells. BIBLIOGRAPHIC REFERENCES: Halmi, N.S., J.A. Parsons, S.L. Erlandsen and T. Duello: Prolactin and growth hormone cells in the human hypophysis: A study with immunoenzyme histochemistry and differential staining. Cell Tissue Res. 158:497-507, 1975. Moriarty, G.C., N.S. Halmi and C.M. Moriarty: The effects of stress on the cytology and immunocytochemistry of pars intermedia cells in the rat pituitary. Endocrinology 96:1426-1436, 1975.